Fluid-cooled LED-based lighting methods and apparatus for controlled agricultural environments

ABSTRACT

A lighting fixture has an extruded aluminum housing, at least one light source mechanically supported by the extruded aluminum housing, and at least one copper pipe thermally coupled to the extruded aluminum housing to carry a fluid coolant. During operation of the lighting fixture, the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture, and the fluid coolant does not contact the extruded aluminum housing. In one example, a copper fluid coolant circuit is thermally coupled to the housing to contain the fluid coolant, and the lighting fixture does not contain any internal seals or internal O-rings for the fluid coolant.

CROSS-REFERENCE TO RELATED PATENT APPLICATION(S)

This application is a continuation of, and claims priority to, U.S. application Ser. No. 17/141,173, filed on Jan. 4, 2021, entitled “FLUID-COOLED LED-BASED LIGHTING METHODS AND APPARATUS FOR CONTROLLED AGRICULTURAL ENVIRONMENTS HAVING A VERTICALLY-STACKED MULTIPLE-LEVEL GROWING AREA,” which, in turn, is a continuation of, and claims priority to, U.S. application Ser. No. 16/114,088, filed on Aug. 27, 2018, entitled “FLUID-COOLED LED-BASED LIGHTING METHODS AND APPARATUS FOR CONTROLLED ENVIRONMENT AGRICULTURE,” which, in turn, claims a priority benefit to U.S. Provisional Application Ser. No. 62/550,379, filed on Aug. 25, 2017, entitled “WATER-COOLED LED-BASED LIGHTING METHODS AND APPARATUS FOR CONTROLLED ENVIRONMENT AGRICULTURE,” and U.S. Provisional Application Ser. No. 62/635,499, filed on Feb. 26, 2018, entitled “WATER-COOLED LED-BASED LIGHTING METHODS AND APPARATUS FOR CONTROLLED ENVIRONMENT AGRICULTURE.” Each of the aforementioned applications is incorporated herein by reference in its entirety.

BACKGROUND

Controlled Environment Agriculture (CEA) is the process of growing plants in a controlled environment where various environmental parameters are monitored and adjusted to improve the quality and yield of the plants grown. Compared to conventional approaches of plant cultivation, CEA may enable year-round production of plants, insensitivity to variable weather conditions, reduce pests and diseases, and reduce the amount of resources consumed on a per plant basis. A controlled agricultural environment is typically enclosed, at least in part, by a building structure such as a greenhouse, a grow room, or a covered portion of a field in order to provide some degree of control over environmental conditions. One or more artificial lighting systems are often used in such controlled agricultural environments to supplement and/or replace natural sunlight that may be obstructed by the building structure or insufficient during certain periods of the year (e.g., winter months). Various types of artificial lighting systems may be used including, but not limited to, a high intensity discharge lamp, a light emitting diode (LED), and a fluorescent lamp.

SUMMARY

The present disclosure is directed to various implementations of a fluid-cooled light emitting diode (LED)-based lighting fixture (also referred to hereafter as a “lighting fixture”) for Controlled Environment Agriculture (CEA), respective components of the lighting fixture, and methods relating to the same. The lighting fixture may be coupled to a fluid cooling system (also referred to hereafter as a “coolant circuit”) that flows fluid coolant through the lighting fixture to capture heat generated by one or more LED modules in the lighting fixture. In this manner, heat generated by the lighting fixture may be removed from the controlled agricultural environment, thus reducing the cooling load and improving energy efficiency. The lighting fixture described herein may be coupled to one or more other lighting fixtures in a daisy-chain configuration where plumbing, electrical power, and communication connections are shared to facilitate the creation of a continuous electrical circuit and coolant circuit. In some implementations, the lighting fixture may be coupled to a hydronics system that utilizes waste heat generated by the lighting fixture (and extracted from the lighting fixture by the coolant circuit) for various applications such as regulating the temperature of the controlled agricultural environment or a space near the controlled agricultural environment. The lighting fixture may also function as an integrated sensor platform by providing electrical power and data communication connections to one or more sensors that may monitor various environment conditions of the controlled agricultural environment.

In one exemplary implementation, a lighting fixture includes a frame (also referred to herein as a “housing”) to mechanically support and house various components of the lighting fixture. A light spine is formed onto the frame with features to mechanically couple and secure the lighting fixture to a support structure disposed in the controlled agricultural environment. The frame includes one or more channels and corresponding coolant pipes that fit into the one or more channels. The coolant pipes are formed from copper and used to flow fluid coolant through the lighting fixture to remove heat. One or more LED modules are disposed on the frame to emit photosynthetically active radiation (PAR) for growing plants. A processor is coupled to the frame to facilitate the operation of the lighting fixture with functions including power conversion, network connectivity, and data processing. One or more electrical power ports are disposed on the frame to supply electrical power from an external source (e.g., a building electrical supply system) to various components of the lighting fixture including the LED modules, the processor, and auxiliary devices coupled to the lighting fixture. One or more communication ports are disposed on the frame to facilitate electrical communication and data transmission.

In some implementations, a coolant pipe may be press-fit or crush-fit into a channel of a frame to improve thermal contact, thereby increasing the amount of heat removed by the fluid coolant flowing through the lighting fixture. The coolant pipe of the lighting fixture may be coupled to another coolant pipe of another lighting fixture using push-to-connect plumbing fittings. In this manner, multiple lighting fixtures may be coupled to form a continuous coolant circuit. One or more pumps, regulators, and/or valves may be incorporated into the coolant circuit to generate and direct the fluid coolant through the coolant circuit. A heat rejection device, such as a cooling tower, may also be incorporated into the coolant circuit to remove heat from fluid coolant, thus reducing the temperature of the fluid coolant for reuse in the coolant circuit. The coolant circuit may also be used to remove heat from other components in the controlled agricultural environment, such as a dehumidifier.

In some implementations, a coolant circuit having multiple lighting fixtures may be coupled to a hydronics system to recycle waste heat generated by the lighting fixtures and captured by the fluid coolant. The hydronics system may distribute heat to regulate the temperature of at least a portion of the controlled agricultural environment (e.g., a growing area) or another space near the controlled agricultural environment (e.g., a residential building, a cogeneration plant, a factory). The hydronics system may include a fluid storage tank to store fluid coolant and one or more piping subsystems to direct relatively cool fluid coolant and relatively hot fluid coolant through the coolant circuit and/or other spaces. Fluid coolant may also be stored at various temperatures for later distribution and/or to regulate the temperature of the fluid coolant.

In some implementations, a controlled agricultural environment with one or more fluid-cooled LED-based lighting fixtures does not require additional cooling or air-conditioning. In other words, excess heat generated in the environment from a variety of heat sources (e.g., the lighting fixtures, the plants themselves, walls of a building structure constituting the environment, one or more dehumidifiers) is effectively captured by the fluid coolant and removed by a heat rejection device (e.g., a cooling tower) or recycled in a hydronics system. By significantly reducing, or in some instances eliminating, the need for air-conditioning, a significant source of required energy for the controlled agricultural environment is accordingly significantly reduced or eliminated. The energy savings may lead to substantial reductions in energy costs for controlled agricultural environments on a variable energy budget or increase the energy available to grow larger and crops and larger crop yields for controlled agricultural environments on a fixed energy budget. For example, at least a portion of the energy budget formerly used for cooling/air-conditioning may instead be used for additional artificial lighting to provide PAR and thereby promote plant growth for a greater number of plants.

In various implementations, the lighting fixture disclosed herein may include one or more communication and/or auxiliary power ports, for example, to provide auxiliary DC power to one or more auxiliary devices coupled to the port(s). Example of such ports include, but are not limited to, one or more Power over Ethernet (PoE) ports and/or one or more Universal Serial Bus (USB) ports to communicatively couple multiple lighting fixtures together and/or support operation of one or more auxiliary devices (e.g., sensors, actuators, or other external electronic devices). Examples of various sensors that may be coupled to one or more lighting fixtures via one or more of the PoE or USB ports include, but is not limited to, air temperature sensors, near-infrared (NIR) leaf moisture sensors, hyperspectral cameras, finite spectral cameras, IR leaf temperature sensors, relative humidity sensors, and carbon dioxide sensors. Other examples of auxiliary devices that may be coupled to one or more lighting fixtures via PoE or USB ports include, but are not limited to, one or more fans, security cameras, smart phones, and multi-spectral cameras (e.g., to analyze soil moisture, nutrient content, leaves of the plants). In this manner, various auxiliary devices may be particularly distributed in the controlled agricultural environment due to the flexible placement of communication ports on the lighting fixtures.

In some implementations, the processor of the lighting fixture may be used to control one or more auxiliary devices and/or process data from the auxiliary devices. The processor may then utilize the data to adjust and control operation of one or more lighting fixtures (e.g., adjusting the PAR output from the lighting fixture) one or more coolant circuits or other fluid coolant loops (e.g., adjusting the fluid flow through the coolant circuit/lighting loop, heating loop, and cooling loops), one or more fans, one or more dehumidifiers, or one or more air conditioners in the controlled agricultural environment. In some implementations, various environmental conditions are measured and controlled to provide target vapor pressure deficits in the environment.

In some implementations, the lighting fixture may be used in a leased lighting system where a customer pays a recurring fee to rent and operate one or more lighting fixtures. In one exemplary implementation, the lighting fixture may be communicatively coupled to a license server that controls the amount of time the lighting fixtures operates according to payments by the customer. Encryption keys and a token exchange with a license server may be used operate the leased lighting system for a controlled agricultural environment.

In sum, one example implementation is directed to a A fluid-cooled LED-based lighting fixture, comprising: an extruded aluminum frame including at least a first channel, a second channel, and at least one enclosed cavity formed therein, the extruded aluminum frame further including a fin protruding from the frame and having a plurality of holes to facilitate mechanical coupling of the lighting fixture to at least one support structure; at least one LED light source mechanically supported by the extruded aluminum frame; a first copper pipe to carry a fluid coolant to extract heat generated by at least the at least one LED light source during operation of the lighting fixture, wherein the first copper pipe is press-fit into the first channel of the extruded aluminum frame so as to establish a first thermal connection between the first copper pipe and the extruded aluminum frame; a second copper pipe to carry the fluid coolant, wherein the second copper pipe is press-fit into the second channel of the extruded aluminum frame so as to establish a second thermal connection between the second copper pipe and the extruded aluminum frame; control circuitry, disposed in the at least one enclosed cavity of the extruded aluminum frame, to receive AC power and to control the at least one LED light source; and a plurality of ports, electrically coupled to at least some of the control circuitry, to provide DC power to at least one auxiliary device coupled to at least one of the plurality of ports.

Another example implementation is directed to a method for controlling an agricultural environment, the method comprising: A) flowing a fluid coolant in a coolant circuit, wherein the coolant circuit comprises at least one LED-based lighting fixture from which the fluid coolant extracts fixture-generated heat as the fluid coolant flows in the coolant circuit through the at least one LED-based lighting fixture and at least one hydronics loop, coupled to the at least one LED-based lighting fixture, to facilitate temperature regulation in at least a portion of the agricultural environment; B) irradiating a plurality of plants with photosynthetically active radiation (PAR) output by at least one LED-based lighting fixture; and C) sensing at least one condition in the agricultural environment via at least one sensor communicatively coupled to the at least one LED-based lighting fixture.

Another example implementation is directed to a method for controlling an agricultural environment, the method comprising: A) flowing a fluid coolant in a coolant circuit, wherein the coolant circuit comprises at least one LED-based lighting fixture from which the fluid coolant extracts fixture-generated heat as the fluid coolant flows in the coolant circuit through the at least one LED-based lighting fixture and at least one hydronics loop, coupled to the at least one LED-based lighting fixture, to facilitate temperature regulation in at least a portion of the agricultural environment; B) irradiating a plurality of plants with photosynthetically active radiation (PAR) output by at least one LED-based lighting fixture; C) sensing at least one condition in the agricultural environment via at least one sensor communicatively coupled to the at least one LED-based lighting fixture, wherein the at least one sensor includes least one of: an air temperature sensor; a near infrared (NIR) sensor; a relative humidity sensor; a camera; a carbon dioxide (CO2) sensor; and an infrared (IR) sensor; and D) controlling at least one of 1) the PAR output by the at least one LED lighting fixture and 2) a flow of the fluid coolant in at least one of the at least one LED lighting fixture and the hydronics loop, based at least in part on the at least one sensed condition in C), wherein: the at least one LED-based lighting fixture includes at least a first copper pipe and a second copper pipe forming at least a portion of the coolant circuit; and A) comprises flowing the fluid coolant in opposite directions in the first copper pipe and the second copper pipe, respectively.

It should be appreciated that all combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are contemplated as being part of the inventive subject matter disclosed herein. It should also be appreciated that terminology explicitly employed herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent with the particular concepts disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

The skilled artisan will understand that the drawings primarily are for illustrative purposes and are not intended to limit the scope of the inventive subject matter described herein. The drawings are not necessarily to scale; in some instances, various aspects of the inventive subject matter disclosed herein may be shown exaggerated or enlarged in the drawings to facilitate an understanding of different features. In the drawings, like reference characters generally refer to like features (e.g., functionally similar and/or structurally similar elements).

FIG. 1 is an illustration of a conventional controlled agricultural environment where one or more HPS lamps are used.

FIG. 2 is an illustration of a conventional controlled agricultural environment where one or more conventional LED-based lighting fixtures are used.

FIG. 3 is an illustration of a controlled agricultural environment where one or more fluid-cooled LED-based lighting fixtures are retrofit into a pre-existing environment, according to some implementations of the disclosure.

FIG. 4 is an illustration of a controlled agricultural environment where one or more fluid-cooled LED-based lighting fixtures are coupled to a hydronics system, according to some implementations of the disclosure.

FIG. 5 is a block diagram of a lighting fixture, according to some implementations of the disclosure.

FIG. 6A is a circuit diagram detailing a first half of an exemplary LED module of a lighting fixture, according to some implementations of the disclosure.

FIG. 6B is a circuit diagram detailing the second half of the exemplary LED module of FIG. 6B.

FIG. 7A shows a bottom, front perspective view of a lighting fixture, according to some implementations of the disclosure.

FIG. 7B shows front, bottom, left side, and right side views of the lighting fixture of FIG. 7A.

FIG. 7C shows a cross-sectional view of the lighting fixture of FIG. 7B along the plane A-A.

FIG. 8A shows a top perspective view of a first lighting fixture coupled to a second lighting fixture and a support structure, according to some implementations of the disclosure.

FIG. 8B shows a perspective view of a controlled agricultural environment showing multiple rows of fluid-cooled LED-based lighting fixtures coupled together forming a continuous electrical and coolant circuit, according to some implementations of the disclosure.

FIG. 9A shows an exemplary hydronics system including a fluid storage tank and multiple piping subsystems such as a lighting loop, a heating loop, and a cooling loop, according to some implementations of the disclosure.

FIG. 9B shows a portion of an exemplary hydronics system coupled to a lighting fixture and a growing area, according to some implementations of the disclosure.

FIG. 9C shows a controlled agricultural environment where one or more fluid-cooled LED-based lighting fixtures are disposed in a vertically-stacked multiple-level growing area and coupled to a hydronics system, according to some implementations of the disclosure.

FIG. 10 shows a side view of a controlled agricultural environment with a plurality of fluid-cooled LED-based lighting fixtures and a plurality of sensors to facilitate monitoring of environmental conditions, according to some implementation of the disclosure.

FIG. 11A is a block diagram detailing various electronics components of a processor including a control board, a network board, and a single board computer, according to some implementations of the disclosure.

FIG. 11B is a block diagram providing additional detail of the control board of FIG. 11A.

FIG. 11C is a block diagram providing additional detail of the network board of FIG. 11A.

FIG. 12A is a circuit diagram detailing various electronic components of a network board, according to some implementations of the disclosure.

FIG. 12B is an expanded view of the Ethernet switch of FIG. 12A.

FIG. 12C is an expanded view of the PoE port of FIG. 12A.

FIG. 12D is a circuit diagram of the PoE controller of FIG. 12A.

FIG. 13 is a circuit diagram of a single board computer, according to some implementations of the disclosure.

FIG. 14A is a circuit diagram detailing various electrical components of a control board, according to some implementations of the disclosure.

FIG. 14B is a circuit diagram detailing the bias and control power supply of the control board of FIG. 14A.

FIG. 14C is a circuit diagram detailing the DC-DC converter of the control board of FIG. 14A.

FIG. 14D is a circuit diagram detailing the AC line sensor of the control board of FIG. 14A.

FIG. 14E is a circuit diagram detailing the DSP of the control board of FIG. 14A.

FIG. 14F is a circuit diagram detailing the temperature sensor circuitry of the control board of FIG. 14A.

FIG. 14G is a circuit diagram detailing the boost circuit of the control board of FIG. 14A.

FIG. 14H is a circuit diagram further detailing the boost circuit of FIG. 14G.

FIG. 15A is a flow diagram of a contract enforcement method, according to some implementations of the disclosure.

FIG. 15B is a flow diagram of a method to update a license in a leased lighting system, according to some implementations of the disclosure.

DETAILED DESCRIPTION

Following below are more detailed descriptions of various concepts related to, and implementations of, fluid-cooled LED-based lighting methods and apparatus for controlled environment agriculture. It should be appreciated that various concepts introduced above and discussed in greater detail below may be implemented in numerous ways. Examples of specific implementations and applications are provided primarily for illustrative purposes so as to enable those skilled in the art to practice the implementations and alternatives apparent to those skilled in the art.

The figures and example implementations described below are not meant to limit the scope of the present implementations to a single embodiment. Other implementations are possible by way of interchange of some or all of the described or illustrated elements. Moreover, where certain elements of the disclosed example implementations may be partially or fully implemented using known components, in some instances only those portions of such known components that are necessary for an understanding of the present implementations are described, and detailed descriptions of other portions of such known components are omitted so as not to obscure the present implementations.

Controlled Environment Agriculture (CEA) is the process of growing plants in a controlled environment where various environmental parameters, such as lighting, temperature, humidity, nutrient levels, and carbon dioxide (CO₂) concentrations are monitored and adjusted to improve the quality and yield of the plants. Compared to conventional approaches of plant cultivation, CEA may enable year-round production of plants, insensitivity to variable weather conditions, reduce pests and diseases, and reduce the amount of resources consumed on a per plant basis. Additionally, CEA may support various types of growing systems including, but not limited to soil-based systems and hydroponics systems.

A controlled agricultural environment is typically enclosed, at least in part, by a building structure such as a greenhouse, a grow room, or a covered portion of a field in order to provide some degree of control over environmental conditions. One or more artificial lighting systems are often used in such controlled agricultural environments to supplement and/or replace natural sunlight that may be obstructed by the building structure or insufficient during certain periods of the year (e.g., winter months). The use of an artificial lighting system may also provide yet another measure of control where the intensity and spectral characteristics of the lighting system may be tailored to improve the photosynthetic rates of plants. Various types of artificial lighting systems may be used including, but not limited to, a high intensity discharge lamp, a light emitting diode (LED), and a fluorescent lamp.

Artificial lighting systems, however, generate heat, which when dissipated into the environment may contribute significantly to the cooling load of the controlled agricultural environment. In order to accommodate the higher cooling load and thus maintain the controlled agricultural environment within a desired temperature envelope, the cooling capacity of a cooling system may need to be increased resulting in greater energy consumption. For a controlled agricultural environment on a variable energy budget, greater energy consumption may lead to higher energy costs. Alternatively, for a controlled environment on a fixed energy budget, a larger portion of the energy budget may be consumed by the cooling system, thus reducing the energy and capacity available to support a larger crop size and yield.

To illustrate the impact excess heat generated by an artificial lighting system may have on energy consumption, FIG. 1 shows a conventional controlled agricultural environment with one or more high pressure sodium (HPS) lamps 10, a particular type of high intensity discharge lamp, which irradiates a plurality of plants 900. The exemplary controlled agricultural environment shown in FIG. 1 further includes a dehumidifier 65 to manage the relative humidity of the environment and an air conditioner 85, which may include a fan coil, compressor, and condenser. Energy consumption by the air conditioner 85 generally depends on (1) the total cooling load of the environment and (2) the energy efficiency ratio (EER) of the air conditioner 85. The EER of an air conditioner is defined as the ratio of the cooling capacity (in Watts) to the input power (in Watts) at a given operating point. The EER was calculated with a 35° C. (95° F.) outside temperature and an inside (return air) temperature of 26.7° C. (80° F.) and 50% relative humidity. A higher EER indicates the air conditioner 85 is more efficient.

As shown in FIG. 1 , the HPS lamps 10 may increase the cooling load of the environment by (1) dissipating heat convectively and/or radiatively directly into the environment and (2) increasing the relative humidity of the environment and thus, the power input and resultant heat generated by the dehumidifier 65. The cooling load in this exemplary controlled agricultural environment is about 1315 W. For an EER ranging from 3 to 7, the input power for the air conditioner thus ranges from 450 to 190 W, respectively. Based on the input power to the HPS lamps 10 of 1050 W and the dehumidifier 65 of 265 W, the air conditioner 85 thus consumes about 13% and 26% of the total energy budget, corresponding to an EER of 7 and 3, respectively.

The amount of heat generated may vary depending on the type of lighting system used. However, artificial lighting systems for controlled agricultural environments generally have large power inputs (e.g., greater than 1000 W) in order to sustain a sufficient level of photosynthetically active radiation (PAR). Thus, the heat generated by various types of lighting systems may still constitute a large portion of heat produced within the environment. In another example, FIG. 2 illustrates a conventional controlled agricultural environment where one or more conventional LED-based lighting fixtures 12A and 12B irradiate a plurality of plants 900. In this exemplary controlled agricultural environment, the LED-based lighting fixtures 12A and 12B dissipates heat primarily via convection, which may reduce the power input and heat generated by the dehumidifier 65. In this example, the total cooling load is about 1210 W. For an EER ratio ranging from 3 to 7, the input power for the air conditioner 85 ranges from 405 W to 175 W. Compared to the first example, the use of LED-based lighting fixtures 12A and 12B decreases the total energy budget of the controlled agricultural environment. However, the proportion of energy used by the air conditioner 85 remains similar to the first example at about 13% and 25% for an EER ratio of 7 and 3, respectively. As shown in the two exemplary controlled agricultural environments, artificial lighting systems may generate a substantial amount of heat, which may result in air conditioning systems consuming a significant portion of the total energy budget in a controlled agricultural environment.

The present disclosure is thus directed to a fluid-cooled LED-based lighting fixture. In some implementations, a fluid cooling system may be integrated into the lighting fixture such that a substantial portion of the heat generated by one or more LED's in the lighting fixture is captured by the fluid cooling system. In this manner, the amount of heat transferred to the environment by the lighting fixture may be substantially reduced, thus decreasing the cooling load and the energy input for any air conditioning systems that may be in the controlled agricultural environment. In some implementations, the fluid cooling system may be coupled to a hydronics system to distribute waste heat from the lighting fixture to control the temperature of the growing area or a separate interior space (e.g., a residential building). In some implementations, two or more lighting fixtures may be connected in series, or “daisy-chained,” where electrical and piping connections are shared to support a continuous electrical circuit and coolant circuit. The lighting fixture may also provide electrical connections to power one or more sensors to monitor various environmental conditions. In this manner, the fluid-cooled LED-based lighting fixture may also function as an integrated sensor platform.

To illustrate the benefits of a fluid-cooled LED-based lighting fixture disclosed herein, FIG. 3 shows an exemplary implementation of a controlled agricultural environment 2000A where a lighting fixture 1000 is retrofit into a pre-existing environment that includes a dehumidifier 65 and an air conditioner 85. While not shown explicitly in FIG. 3 , the environment may be constituted, at least in part, by a building structure to house a plurality of plants 900, one or more lighting fixtures 1000, and other equipment. The lighting fixture 1000 is cooled by a fluid coolant 800 that circulates through a coolant circuit 570. Heat carried by the fluid coolant 800 is removed by a cooling tower 557 located outside of the controlled agricultural environment 2000A. The coolant circuit 570 may include one or more pumps, regulators and/or valves 555 to control the flow of the fluid coolant 800 in the coolant circuit 570.

As shown in FIG. 3 , the one or more pumps, regulators, and/or valves 555 may produce a flow of fluid coolant 800 that exhibits a relatively colder temperature Tc upon entry into the lighting fixture 1000 and a relatively hotter temperature Tx upon exit from the lighting fixture 1000. The rise in temperature of the fluid coolant 800 is due, in part, to convective heating of the fluid as it passes through the lighting fixture 1000 due to heat generated from one or more LED modules within the lighting fixture 1000. The fluid coolant 800 may thus be used to capture and transport heat generated by the lighting fixture 1000, which may substantially reduce the cooling load of the environment and the power inputs to the air conditioner 85 and/or the dehumidifier 65. As shown in FIG. 3 , the cooling load for the exemplary controlled agricultural environment 2000A is about 635 W, which is approximately 50% the cooling load in the exemplary controlled agricultural environments shown in FIGS. 1 and 2 . For an EER ranging from 3 to 7, the input power for the air conditioner thus ranges from 210 W to 90 W, respectively. Based on the input power to the lighting fixture 1000 of 1050 W and the dehumidifier 65 of 160 W, the air conditioner 85 thus consumes about 7% and 15% of the total energy budget, corresponding to an EER of 7 and 3, respectively.

Although a cooling tower 557 is shown in FIG. 3 to facilitate evaporative cooling of the heated fluid coolant exiting the lighting fixture 1000, it should be appreciated that various types of heat rejection devices may be employed in the coolant circuit 570 to remove heat from the fluid coolant 800. Some examples of heat rejection devices include, but are not limited to, various types of evaporative coolers, “free” coolers, chillers, dry coolers, air source coolers, ground source heat exchangers, water source heat exchangers, or any combinations of the foregoing.

In another example, FIG. 4 shows an exemplary controlled agricultural environment 2000B where a lighting fixture 1000 is coupled to a coolant circuit 570 that directs the fluid coolant 800 to a hydronics system 501A having multiple plumbing subsystems 700A and 700B (also referred to herein as “hydronics loops”), which regulate and/or maintain the temperature of various portions of the controlled agricultural environment 2000B and/or space near the controlled agricultural environment 2000B (e.g., a hot pool, the growing area) by utilizing the waste heat generated by the lighting fixture 1000 as a heat source. The coolant circuit 570 may receive heat from the lighting fixture 1000 and other environment sources (e.g., a dehumidifier 65, the ambient air) such that excess heat generated in the environment may be substantially removed, thus further improving the energy savings to operate the controlled agricultural environment 2000B. In some implementations, the cooling load may be sufficiently reduced so as to eliminate the need for any air conditioning systems (i.e., there is no air conditioner fan coil, compressor or condenser).

As shown in FIG. 4 , the controlled agricultural environment 2000B may include a dehumidifier 65 to regulate the relative humidity of the environment. The coolant circuit 570 may direct fluid coolant 800 heated by the lighting fixture 1000 into the dehumidifier 65 to further remove heat generated by the dehumidifier 65 in a convective manner similar to the removal of heat from the lighting fixture 1000. The coolant circuit 570 may then direct the fluid coolant 800 to the hydronics loops 700A and 700B, which may be used to heat the plurality of plants 900 and a hot pool, respectively. The coolant circuit 570 may distribute and direct heated fluid coolant 800 in a controlled manner by one or valves 502 before dissipating the remaining heat by the cooling tower 557.

In some implementations, the hydronics system 501A may also be used to regulate the temperature of the ambient environment itself. For example, the hydronics system 501A may be used to heat the controlled agricultural environment 2000B convectively and/or radiatively as the fluid coolant 800 flows through the hydronics system 501. A Furthermore, while FIG. 4 shows a coolant circuit 570 passing through the dehumidifier 65, it should be appreciated that in other implementations the coolant circuit 570 need not include the dehumidifier 65, e.g. the coolant need not flow through the humidifier 65.

An exemplary implementation of a fluid-cooled LED-based lighting fixture 1000 is shown in FIG. 5 . The lighting fixture 1000 may include a frame 1004 to mechanically support and house various components of the lighting fixture 1000. A light spine 1002 may be incorporated onto one or more sides of the frame 1004 with features to mechanically couple and secure the lighting fixture 1000 to a support structure disposed within a controlled agricultural environment. One or more coolant pipes 1006 may be coupled to the frame 1004, where each coolant pipe 1006 may be used to flow a fluid coolant 800 to cool the lighting fixture 1000. One or more LED modules 400 may be disposed on the frame 1004 to emit PAR towards a plurality of plants. A processor 90 may be coupled to the frame 1004 to facilitate the operation of the lighting fixture 1000 including, but not limited to power conversion, network connectivity, and data processing. One or more electrical power ports 1010 may be disposed on the frame 1004 to supply electrical power to various components of the lighting fixture 1000, including, but not limited to the LED modules 400, the processor 90, and other sensors that may be coupled to the lighting fixture 1000. One or more communication ports 1009 may be disposed on the frame 1004 to facilitate electrical communication and data transmission.

The frame 1004 may be a mechanically rigid, hollow structure that forms a substantially enclosed housing. The interior cavity of the frame 1004 may be dimensioned to house a plurality of components in the lighting fixture 1000, such as various electronics in the processor 90. The frame 1004 may include one or more mounting features within the interior cavity to securely couple the plurality components to the frame 1004. For example, the frame 1004 may include one or more slots disposed within the interior cavity of the frame 1004 and arranged so as to mechanically support at least two opposing edges of a printed circuit board. Other mounting features may include, but are not limited to mounting posts and mounting stubs.

One or more removable panels may be included in the frame 1004 to provide access to the interior space. The one or more removable panels may be coupled to a portion of the frame 1004 using various types of coupling mechanisms including, but not limited to screw fasteners, bolt fasteners, clips, and clamps. In some implementations, the frame 1004 may form a sufficiently airtight enclosure or cavity to protect components, e.g., electronics, that may be sensitive to the environmental conditions of the controlled agricultural environment. For example, the controlled agricultural environment may operate at a relative humidity that may cause moisture to condense onto various surfaces of the lighting fixture 1000, causing damage to components including exposed electronics. In instances where the frame 1004 is an airtight enclosure, moisture may be substantially restricted from infiltrating the interior space of the frame 1004 to reduce the likelihood of condensation forming onto components disposed within the frame 1004.

The frame 1004 may also include a recessed portion disposed along at least one side of the frame 1004, e.g., the bottom side, with sidewalls that at least partially surround one or more LED modules 400. The recessed portion may be used to direct light emitted by the one or more LED modules 400 along a preferred direction and angular distribution. For example, the recessed portion may be used to substantially illuminate a growing area containing one or more plants located below the frame 1004. In some implementations, the surface quality and orientation of the interior surfaces of the sidewalls forming the recessed portion may form an integrated reflector to reflect light emitted by the one or more LED modules 400. For example, the interior surfaces of the sidewalls may be polished to reflect light in a substantially specular manner and oriented such that light is reflected towards a preferred direction, e.g., the growing area.

The frame 1004 may also include one or more channels formed along one or more sides of the frame 1004 where each channel may be used to secure a corresponding coolant pipe 1006 to the frame 1004. The cross-sectional shape of the channel may be substantially similar to the cross-sectional shape of the coolant pipe 1006 to facilitate insertion of the coolant pipe 1006 into the channel. The coolant pipe 1006 may be secured to the channel of the frame 1004 using several approaches. For example, the cross-section dimensions of the channel may be equal to or smaller than the cross-sectional dimensions of the coolant pipe 1006 to facilitate a press fit where the coolant pipe 1006 is secured to the channel via friction. In other examples, the coolant pipe 1006 may be clamped to the frame 1004 using one or more clamps, which may include, but are not limited to zip ties and clamps with a worm drive fastener. The clamps may be removable to allow replacement of the coolant pipes 1006. The surface of the one or more channels may also be polished to improve thermal contact with the coolant pipe 1006, thus enabling greater heat dissipation into the fluid coolant 800. In yet other examples, the coolant pipes 1006 may be adhered or bonded to the frame 1004 using various methods including, but not limited to adhesive bonding, welding, and brazing. Thermal interface material may also be disposed between the channel and the coolant pipe to improve thermal contact.

The frame 1004 may also be, at least in part, thermally conducting to transfer heat from the one or more LED modules 400 to the coolant pipe 1006. In particular, a first portion of the frame 1004 disposed between the LED module 400 and the coolant pipe 1006 may be formed from a thermally conducting material with dimensions to (1) reduce the distance between the LED module 400 and the coolant pipe 1006 and (2) increase the lateral cross-sectional area between the LED module 400 and the coolant pipe 1006. In this manner, the thermal resistance between the LED module 400 and the coolant pipe 1006 may be reduced. In some implementations, the frame 1004 may be formed entirely from the thermally conducting material to simplify manufacture and assembly. In some implementations, the first portion of the frame 1004 may be formed from a thermally conducting material while the remainder of the frame 1004 is formed from another material, such as a polymer in order to reduce material costs.

The frame 1004 may be formed from various metals, ceramics, polymers, or composites including, but not limited to, copper, aluminum, stainless steel, carbon steel, polyethylene, acrylic, and porcelain. Depending on the materials used to form the frame 1004, various method of manufacture may be utilized including, but not limited to extrusion, sandcasting, milling, injection molding, and manual molding. For instances where the frame 1004 is assembled form multiple parts, various coupling mechanisms may be used for assembly including, but not limited to snap fits, screw fasteners, bolt fasteners, adhesives, brazing, and welding.

The light spine 1002 may be used to secure the lighting fixture 1000 to a support structure in the controlled agricultural environment. The support structure may be various types of structures including, but not limited to a railing, a suspended platform, a ceiling, and a wall. The light spine 1002 may be a protruding fin formed onto the frame 1004 that includes one or more holes of varying size to accommodate different sizes and types of coupling mechanisms used to secure the lighting fixture 1000 to the support structure. The coupling mechanisms may include, but are not limited to bolt fasteners, screw fasteners, hooks, and shackles. The light spine 1002 may be dimensioned to span the length of the frame 1004, thus providing multiple locations along the frame 1004 to couple the lighting fixture 1000 to the support structure in a stable manner. For example, the light spine 1002 may be disposed on the top side of the frame 1004 with a length that spans the length of the frame 1004. The light spine 1002 may include a plurality of holes where the center axis of each hole is parallel to the top side of the frame 1004. Multiple bolt fasteners may be installed at each end and the center of the light spine 1002 to secure the lighting fixture 1000 to a sidewall of a support structure. Multiple light spines 1002 may also be distributed along the length of the frame 1004 or on multiple sides of the frame 1004 to allow the lighting fixture 1000 to be coupled to different support structures.

As described above, the coolant pipe 1006 may be used to flow fluid coolant 800 to capture heat generated by the LED module 400. The coolant pipe 1006 may be dimensioned to have a length longer than the frame 1004 such that a portion of the coolant pipe 1006 may extend beyond the sides of the frame 1004 to facilitate coupling of the coolant pipe 1006 to a pipe from a coolant circuit, a hydronics system, or another lighting fixture 1000. Various types of coupling mechanisms may be used to couple the coolant pipe 1006 to another pipe including, but not limited to threaded fittings, where the ends of the coolant pipe 1006 have corresponding threads, and bolt fasteners, where the end of the coolant pipe 1006 have a flange that mates to a corresponding flange on another pipe. In a preferred implementation, push-to-connect plumbing fittings may be used as a coupling mechanism where the ends of the coolant pipe 1006 are left bare. In this manner, internal seals and O-rings do not need to be used.

Multiple coolant pipes 1006 may be incorporated into the frame 1004 where each coolant pipe 1006 may be used to flow fluid coolant 800 along the same or opposing directions. For example, the lighting fixture 1000 may include two coolant pipes 1006 disposed on opposing sides of the frame 1004. For a lighting fixture 1000 that supports multiple LED modules 400, an opposing flow configuration (e.g., fluid coolant 800 flows in opposing directions between the two coolant pipes 1006) may more uniformly remove heat from the multiple LED modules 400. In comparison, a same flow configuration will result in more heat removed from the LED module 400 closest to the fluid coolant 800 input and less heat removed from the LED module 400 furthest from the fluid coolant 800 input. Additionally, the opposing flow configuration may more readily facilitate implementation of a closed coolant circuit. For example, the two coolant pipes 1006 may be connected at one end by a plumbing fitting such that fluid coolant 800 entering the lighting fixture 1000 flows through a first coolant pipe 1006 and then a second coolant pipe 1006 serially before exiting the lighting fixture 1000 on the same side.

The coolant pipe 1006 may be formed from various materials including copper, aluminum, and stainless steel. In a preferred implementation, the coolant pipes 1006 may be formed from copper to reduce algae growth, fouling, and corrosion. Thus, by coupling copper coolant pipes 1006 using the push-to-connect plumbing fittings described above, the fluid coolant 800 may pass through a coolant circuit made up of only copper without contacting other materials in the lighting fixture (e.g., an aluminum frame 1004).

The cross-sectional dimensions of the coolant pipe 1006 may vary depending on multiple factors including, but not limited to a desired flow rate, fluid coolant properties (e.g., dynamic viscosity, density), and a desired type of flow. For example, it may be desirable for the fluid coolant to be in a turbulent flow regime, which engenders a higher heat transfer coefficient, thus dissipating more heat from the lighting fixture 1000. In some implementations, the cross-sectional dimensions of the coolant pipe 1006 may be chosen such that a particular Reynold's number, Re, is greater than a desired threshold (e.g., Re>4000 for turbulent flow) for a given pump power and coolant circuit geometry. The interior surface of the coolant pipe 1006 may also be roughened to increase the surface area and the convective heat transfer coefficient. The effective depth and pitch of the interior surface roughness may be chosen so as to not substantially increase pumping requirements (e.g., due to a larger pressure drop) and maintains wettability of the interior surface to the fluid coolant 800 (e.g., remains hydrophilic, oleophilic).

The fluid coolant 800 used to capture and carry heat from the lighting fixture 1000 may be chosen based on several factors. First, it is preferable for the fluid coolant 800 to exhibit a high thermal conductivity and a high specific heat in order to increase heat dissipation from the LED module 400 to the fluid coolant 800. Second, the fluid coolant 800 should remain in a liquid phase within the operating temperature and pressure range of the controlled agricultural environment. For example, the fluid coolant 800 should not freeze or boil as it passes through the lighting fixture 1000, the coolant circuit, the hydronics system, or a cooling tower. Third, the fluid coolant 800 should also be chosen so as not to substantially corrode the coolant pipe 1006. For controlled agricultural environments, the fluid coolant 800 may be various fluids including, but not limited to water, mineral oil, glycol, and mixtures.

The lighting fixture 1000 also may include one or more communication and/or auxiliary power ports, for example, to provide auxiliary DC power to one or more auxiliary devices coupled to the port(s), and/or facilitate communications between the lighting fixture and the one or more auxiliary devices. Example of such ports include, but are not limited to, one or more Power over Ethernet (PoE) ports and/or one or more Universal Serial Bus (USB) ports.

For example, the lighting fixture 1000 may include at least one electrical power port 1010 to supply electrical power to various components in the lighting fixture 1000 (e.g., the LED module 400) and/or various components electrically coupled to the lighting fixture 1000 (e.g., other lighting fixtures 1000 or auxiliary sensors). The electrical power port 1010 may receive as input alternating current (AC) power, such as from a building electrical supply system, which may be converted into direct current (DC) power via the processor 90. The processor 90 may include electronics to facilitate conversion between DC and AC power, as will be discussed in greater detail below.

One or more communication ports 1009 may also be used in the lighting fixture 1000 to facilitate data transmission to and from the lighting fixture 1000. For example, the communication port 1009 may be used to remotely control various aspects of the lighting fixture 1000 including, but not limited to adjustments to electrical power (e.g., high voltage and low voltage modes), adjustments to the spectral content of the light emission (e.g., directing more power to blue or red LED elements), and commands to operate auxiliary sensor devices (e.g., frequency of data recording). In another example, the communication port 1009 may be used to send various status and monitoring data to a remote user including, but not limited to electrical power consumption, temperature, and data measured by auxiliary sensor devices. The data received and transmitted by the communication port 1009 may be managed, in part, by the processor 90, as will be discussed in more detail below.

The communication port 1009 may accommodate various types of electrical cabling including, but not limited to universal serial bus (USB) cables and Power over Ethernet (PoE) cables. In some implementations, multiple communication ports 1009 including both USB and PoE ports may be used to enable greater flexibility and compatibility with more types of cabling and auxiliary devices. One or more communication ports 1009 may be disposed on one or more sides of the frame 1004. For example, a set of communication ports 1009 may be disposed on opposite sides of the frame 1004 (e.g., left and right sides or front and rear sides) to facilitate connectivity between a plurality of lighting fixtures 1000 in a daisy-chain configuration. Communication ports 1009 may also be disposed on the frame 1004 where auxiliary sensors are likely to be deployed. For example, communication ports 1009 may be disposed on the bottom side of the frame 1004 to provide electrical connection to auxiliary sensors that are used to monitor ambient conditions near the plants located below the lighting fixture 1000. In some implementations, the communication port 1009 may also supply DC power. For example, the lighting fixture 1000 may include a USB port that may electrically power an auxiliary sensor device and receive data measured by the auxiliary sensor device through the same communication port 1009.

The LED module 400 may include one or more LED elements arranged into an array. The one or more LED elements of the LED module 400 may each emit light at a particular wavelength such that in combination, the LED module 400 irradiates plants with light at multiple wavelengths tailored to improve various aspects related to the growth of plants and operation of the controlled agricultural environment including, but not limited to improving photosynthetic rates of the plants, growth modification, and ultraviolet (UV) sterilization. The one or more LED elements may be assembled onto the frontside of a printed circuit board. An exemplary circuit layout of an LED module 400 according to one inventive implementation is shown in FIGS. 6A and 6B, which illustrates the respective halves 400A1 and 400A2 of the LED module 400A. As shown, the LED module 400A may include multiple LED elements that are distributed across the printed circuit board.

The printed circuit board may be a metal core printed circuit board (MCPCB) to facilitate heat dissipation generated by the one or more LED elements. The LED module 400 may be coupled to the frame 1004 such that the backside of the printed circuit board is in contact with the bottom side of the frame 1004 located in the recessed portion as described above. The LED module 400 may be coupled to the frame 1004 using various coupling mechanisms including, but not limited to screw fasteners, bolt fasteners, clips, and clamps. The coupling mechanism may be adjusted such that a clamping force is applied to the LED module 400, thus improving the thermal contact between the LED module 400 and the frame 1004. Additionally, thermal interface material may also be placed between the LED module 400 and the frame 1004 (e.g., at MCPCB interface 1011) to improve thermal contact.

In some implementations, the lighting fixture 1000 may also include an optic located on the recessed portion of the frame 1004, which covers the LED module 400. The optic may be used to modify the direction and angular distribution of the light emitted by the LED module 400. For example, a portion of the optic may have a convex surface to focus light emitted from the LED module 400 onto plants located directly below the lighting fixture 1000. The optic may be coupled to the frame 1004 using various coupling mechanisms including, but not limited to screw fasteners, bolt fasteners, clips, and clamps. In some implementations, the optic may form a substantially airtight enclosure around the LED module 400, thus substantially isolating the LED module 400 from the ambient environment in the controlled agricultural environment. Similar to the airtight enclosure that may be formed by the frame 1004, the optic may reduce moisture infiltration, thus reducing the risk of condensation damaging the LED module 400.

An exemplary lighting fixture 1000 according to one inventive implementation is shown in FIGS. 7A-7C. FIG. 7A shows a bottom perspective view of the lighting fixture 1000 and FIG. 7B shows a front, bottom, left and right side view of the lighting fixture 1000. As shown, the lighting fixture 1000 includes a frame 1004 dimensioned to support three LED modules 400A, 400B, and 400C positioned in a row and disposed on the bottom side of the frame 1004. A light spine 1002 may be formed on the top of the frame 1004 that substantially spans the entire length of the frame 1004. The light spine 1002 may include a plurality of different sized holes to facilitate coupling of the lighting fixture 1000 to a support structure in the controlled agricultural environment. The left and right-side panels of the frame 1004 may be secured by a plurality of screw fasteners and hence, may be removed to allow access into the interior cavity of the frame 1004. The left side panel of the frame 1004 may include two communication ports 1009, e.g., a USB port 1012A and a PoE port 1008C. The right-side panel of the frame 1004 may also include two communication ports 1009, e.g., two PoE ports 1008A and 1008B, as well as an electrical power port 1010. Two communication ports, e.g., a USB port 1012B and a PoE port 1008D, may be disposed on the bottom side of the frame 1004 to facilitate connectivity to auxiliary senor devices that may be used to monitor ambient conditions near the plants. The lighting fixture 1000 also includes two coolant pipes 1006A and 1006B disposed along the front and rear sides of the frame 1004. The frame 1004 may be formed from an aluminum extrusion to include a corresponding pair of channels. The coolant pipes 1006A and 1006B, which may be formed form copper, may be press-fit or crush-fit into the corresponding channels. In this manner, the likelihood that fluid coolant flowing through the coolant pipes 1006A and 1006B contacts the frame 1004 is substantially reduced.

FIG. 7C shows a cross-sectional view of the lighting fixture 1000 where the coolant pipes 1006A and 1006B are shown to be press-fit into the channels of the frame 1004. Thermal interface material 1007 may be disposed between the channels and the coolant pipes 1006A and 1006B to improve thermal contact. The LED modules 400A-400C are disposed substantially in a recessed portion of the bottom side of the frame 1004 and in close proximity to the coolant pipes 1006A and 1006B to facilitate heat dissipation. As shown, a small portion of the frame 1004, which is formed from a thermally conducting material, is present between the coolant pipes 1006A and 1006B and the LED modules 400A-400C. FIG. 7C also shows mounting features 1014 used to support various control circuitry boards 100, 200, and 300, which are collectively referred to hereafter as a processor 90. The mounting features 1014 are a pair of protruding slots disposed along the front and rear sides of the frame 1004, which are dimensioned to support the opposing edges of the processor 90. The processor 90 is positioned above the coolant pipes 1006A and 1006B and LED modules 400A-400C in order to reduce thermal effects due to heat generated by the LED modules 400A-400C. An optic 1020 is also included, which may be coupled to the frame 1004 via a plurality of screw fasteners. The optic 1020 may be a transparent lens with a convex surface used to redirect light emitted by the LED modules 400A-400C along a desired direction and angular distribution. The optic 1020 may also substantially enclose and isolate the LED modules 400A-400C from the surrounding ambient environment.

As described above, the lighting fixture 1000 may be coupled to other lighting fixtures 1000 in a daisy-chain configuration where electrical and piping connections are shared to facilitate assembly of a continuous electrical circuit and coolant circuit. For the coolant circuit, the daisy-chain configuration may be in series where the fluid coolant 800 exiting from one lighting fixture 1000 flows into a subsequent lighting fixture 1000 within the daisy-chain. The temperature of the fluid coolant 800 may increase further due to heat generated from the LED modules 400 of the subsequent lighting fixture 1000. It should be appreciated that so long as the temperature of the coolant fluid 800 is less than the temperature of the LED modules 400 in the lighting fixture 1000, the fluid coolant 800 may still capture heat from the lighting fixture 1000. Furthermore, in some implementations, heat rejection devices may be interspersed along the coolant circuit to reduce the temperature of the fluid coolant 800 and maintain sufficient heat dissipation as the fluid coolant 800 passes through multiple lighting fixtures 1000. An exemplary implementation detailing the manner in which two lighting fixtures 1000 and 1000-B may be coupled in a daisy-chain configuration is shown in FIG. 8A. In some implementations, the lighting fixture 1000 may be coupled to a support structure 999 using a bolt fastener 1027 placed through a hole in the light spine 1002 and secured to the side of the support structure 999 as shown in FIG. 8A.

The coolant pipes 1006A and 1006B of the lighting fixture 1000 may be coupled to a corresponding set of coolant pipes 1006A-B and 1006B-B from the other lighting fixture 1000-B using one or more intermediate pipes. As shown in FIG. 8A, the pair of coolant pipes 1006B and 1006B-B (1006A and 1006A-B) may be connected via a single intermediate pipe 1040B (1040A). Each intermediate pipe 1040B (1040A) may have push-to-connect fittings 1025A (1025B) disposed on both ends to facilitate connection to the coolant pipes 1006B and 1006B-B (1006A and 1006A-B). The shape of the intermediate pipe may vary depending on the desired distance and orientation between lighting fixtures 1000 and 1000-B. For example, the length of the intermediate pipe may be longer in order to space the lighting fixtures 1000 and 1000-B further apart to provide greater areal coverage or to traverse a gap separating two separate growing areas. In another example, the intermediate pipe may be curved such that the lighting fixtures 1000 and 1000-B are oriented at an angle relative to one another, e.g., 90 degrees, to accommodate variable shaped growing areas. In yet another example, the intermediate pipe may be substantially U-shaped to couple two parallel rows of lighting fixtures 1000 where the lighting fixtures 1000 and 1000-B are the last lighting fixtures 1000 in each respective row. In this manner, the coolant circuit may be continuous for multiple rows of lighting fixtures 1000.

Electrical power may be supplied to multiple lighting fixtures 1000 through a single power cable. An exemplary power cable 1030 coupled to the lighting fixture 1000 is shown in FIG. 8A. In some implementations, the power cable 1030 may be rated to support a particular electrical power and current input. For example, the power cable 1030 may be rated to supply at least 1000 W of electrical power and up to 15 A of current. Depending on the power and current requirements of the lighting fixture 1000, the power cable 1030 may be used to power multiple lighting fixtures 1000, thus reducing the amount of cabling and the number of electrical terminals (e.g., electrical outlets) that need to be installed in the controlled agricultural environment.

The lighting fixture 1000 may also be communicatively coupled to another lighting fixture 1000 to facilitate transmission of data and control signals to multiple lighting fixtures 1000. As shown in FIG. 8A, an Ethernet cable 1060 may be used to couple the PoE port 1008A of lighting fixture 1000 to the PoE port 1008C-B of lighting fixture 1000-B. Each of the lighting fixtures 1000 and 1000-B may include a processor to manage the flow of data and/or control signals. In some implementations, the lighting fixture 1000 may be used as a piggyback to facilitate the transfer of data and/or control signals to another lighting fixture 1000 located further along the daisy-chain. In this manner, multiple lighting fixtures 1000 spanning a large area may be communicatively coupled to a fewer number of network nodes (e.g., hubs, switches, routers) and without using excessive amounts of network cabling.

An exemplary arrangement of lighting fixtures 1000 in a controlled agricultural environment 2000 is shown in FIG. 8B. Multiple lighting fixtures 1000 may be arranged along a row spanning a growing area defined by the dimensions of a shelf 902A. Each lighting fixture 1000 in the row may be coupled to a support structure 999A disposed above the shelf 902A. The lighting fixtures 1000 in the row may be coupled together in a daisy chain configuration, as described above. Intermediate piping may be used to couple adjacent lighting fixtures 1000 such that fluid coolant 800 may circulate through the multiple lighting fixtures 1000 in a continuous manner from a single inlet and outlet for the row. One or more power cables may be used to supply electrical power to the lighting fixtures 1000. Ethernet cabling may be used to communicatively couple the lighting fixtures 1000 in a serial manner and to a common network node. As shown in FIG. 8B, the controlled agricultural environment 2000 may include multiple rows of lighting fixtures 1000 supported by support structures 999A-999E arranged above corresponding rows of shelves 902A-902E. The controlled agricultural environment 2000 may further include a fan 75, dehumidifiers 65A and 65B, and air conditioning ducts 85A and 85B for one or more air conditioners.

As previously shown in the exemplary controlled agricultural environments 2000A and 2000B in FIGS. 3 and 4 , respectively, the lighting fixture 1000 may be incorporated into a coolant circuit 570 to facilitate the flow of fluid coolant 800 such that heat may be continuously removed from the lighting fixture 1000. In some implementations, the coolant circuit 570 may be designed to substantially remove heat from only the lighting fixture 1000 and is not intended to thermally interact with other components or regions of the controlled agricultural environment 2000A, as shown in the coolant circuit 570 in FIG. 3 for a retrofit application. In some implementations, however, the coolant circuit 570 may include additional piping subsystems designed to redistribute heat to a space near or within the controlled agricultural environment, such as the hydronics loops 700A shown in FIG. 4 for a hydronics application, and/or to store heat captured by the lighting fixture 1000 for later use.

A piping subsystem may be branched from the coolant circuit 570 such that the flow of fluid coolant 800 may be controllably adjusted (e.g., by a valve and a separate pump) without affecting the flow of fluid coolant 800 through the coolant circuit 570 and hence, without affecting the removal of heat from the lighting fixture 1000. However, in some instances, a piping subsystem may be placed in series with the coolant circuit 570 where the piping subsystem is also used on a continual basis. Some exemplary instances of a piping subsystem being used in series with the coolant circuit 570 includes, but is not limited to a heating system for a hot water system in a residential space, storing heat from the fluid coolant 800 in a thermal energy storage system, and charging a battery by converting heat from the fluid coolant 800 into electricity (e.g., using a thermoelectric device).

FIG. 9A shows an exemplary hydronics system 501 that may be used in connection with a coolant circuit 570 as well as in other implementations of a controlled agricultural environment where one or more lighting fixtures 1000 are used. As shown, the hydronics system 501 may include a fluid storage tank 500 to store fluid coolant 800, which may be disposed internally or externally to the controlled agricultural environment. In some implementations, the fluid storage tank 500 may include separate compartments for relatively cooler fluid coolant 800 and relatively hotter fluid coolant 800 with sufficient thermal insulation to substantially thermally isolate the compartments from one another and the surrounding environment. The fluid storage tank 500 may also be dimensioned to have a sufficiently large storage capacity such that the thermal time constant of the fluid storage tank 500 meets a desired rate of change in temperature during operation. For example, it may be desirable for the temperature of the fluid coolant 800 stored in the fluid storage tank 500 to remain substantially unchanged (e.g., 1° C. per hour) throughout the day to reduce fluctuations in the amount of heat supplied to various piping subsystems. However, if adjustments to the fluid coolant 800 temperature are desired, the amount of time needed for the adjustments to occur may be prohibitive due to the long thermal time constant. In such instances, multiple fluid storage tanks 500, each having a smaller capacity and thus a shorter thermal time constant, may be used instead.

Three submersible pumps 560A, 560B, and 560C may be disposed within the fluid storage tank 500 to pump fluid coolant 800 through three corresponding piping subsystems, namely, the coolant circuit 570 (also referred to in FIG. 9A as a “lighting loop”), a heating loop 512, and a cooling loop 514. The lighting loop 570 associated with the pump 560A is responsible for providing relatively cooler fluid coolant from the fluid storage tank 500 to one or more lighting fixtures 1000 (e.g., via the coolant circuit 570 as shown in FIGS. 3 and 4 ) and returning relatively hotter fluid coolant 800 from the one or more lighting fixtures 1000 to the fluid storage tank 500. In this manner, the lighting loop 570 may function as a heat source to heat fluid coolant 800 stored in the fluid storage tank 500 with heat being subsequently distributed to other piping subsystems. In some implementations, the lighting loop 570 may be used to heat at least a portion of the controlled agricultural environment 2000C via natural convection or thermal radiation to regulate and maintain temperature of the portion within a desired temperature envelope.

In some implementations, a secondary heating loop may be incorporated into the lighting loop 570 to more directly and controllably heat a portion of the controlled agricultural environment 2000C that may not be proximate to the lighting loop 570 (e.g., a growing area, as shown in FIG. 4 ). For example, the secondary heating loop may include a pump, a fan, and a fan coil. The pump may generate a flow of relatively hotter fluid coolant 800 through the fan coil, thus heating the fan coil. The fan may then generate a flow of hot air, thus heating the portion of the controlled agricultural environment 2000C via forced convection. In another example, the secondary heating loop may be routed through the root zone of the growing area to heat the soil or nutrient solution to a desired temperature via a combination of convection and conduction (e.g. see the hydronics loop 700A in FIG. 4 ). The secondary heating loop may include a flow controlling device (e.g., a valve) to control the amount of heat added to the portion of the controlled agricultural environment. For example, the secondary heating loop may be coupled to a thermostat that adjusts the heat added according to a day/night cycle.

The heating loop 512 associated with the pump 560B may also be used to heat a portion of the controlled agricultural environment 2000C or another space located separately to the controlled agricultural environment 2000C. For example, the heating loop 512 may be coupled to a heating, ventilation, and air conditioning (HVAC) system in a building to regulate the interior climate of the building, a heating system in a manufacturing plant to offset gas or electricity consumption, or a cogeneration plant to produce electricity and high-grade heat. In some implementations, the heating loop 512 may also be coupled to a heat store 530, which may provide additional capacity to store heat for future use by the controlled agricultural environment 2000C or another space.

The cooling loop 514 associated with the pump 560C may be used to cool the fluid coolant 800 stored in the fluid storage tank 500. In this manner, the temperature of the relatively cooler fluid coolant 800 entering the lighting loop 570 may be regulated and maintained, which may reduce the effects of thermal drift over time where the temperature of the relatively cooler fluid coolant 800 increases, thus reducing the amount of heat removed from the one or more lighting fixtures 1000. In some implementations, the cooling loop 514 may be a piping subsystem that captures heat to an exterior environment via natural convection and radiation along the length of the cooling loop 514. In some implementations, a heat rejection device may be incorporated into the cooling loop 514 to facilitate cooling of the fluid coolant 800. Various types of heat rejection devices may be used including, but not limited to cooling towers (e.g., see the cooling tower 557 in FIG. 3 or FIG. 4 ), evaporative coolers, “free” coolers, chillers, dry coolers, air source coolers, ground source heat exchangers, water source heat exchangers, or any combinations of the foregoing. In some implementations, the cooling loop 514 may also be coupled to a cold store 520, which may provide additional capacity to store relatively cooler fluid coolant 800 for future use by the controlled agricultural environment 2000C or another space.

In various implementations described herein, the temperature of the fluid coolant 800 stored in the fluid storage tank 500 and flowing through the lighting loop 570, heating loop 512, cooling loop 514, and one or more secondary loops coupled to any of the lighting loop 570, heating loop 512, cooling loop 514 may vary within an appreciable temperature range. In some implementations, the temperature of the fluid coolant 800 may range from about 20° C. to about 50° C. The flow rate of the fluid coolant 800 may range from about 1 gallon per minute to about 3 gallons per minute through the lighting loop 570. Similar or significantly different (e.g., higher) flow rates may be used by the heating loop 512 and the cooling loop 514. Furthermore, the various piping subsystems (e.g., the lighting loop 570, the heating loop 512, and the coolant loop 514) may be controlled via at least one of a pump, regulator, and/or valves. The at least one of a pump, regulator, and/or valves may be operated on various time cycles (e.g., daily, weekly, monthly, seasonal, other periodicities, or any combination thereof) to regulate and maintain desired thermal conditions, which may be dynamic as a function of time, in the controlled agricultural environment 2000C.

Additionally, while three piping subsystems are shown in FIG. 9A, it should be appreciated that any number and combination of piping subsystems may be used with the coolant circuit 570. For example, one or both of the heating loop 512 and the cooling loop 514 may be used in conjunction with the lighting loop 570. It should also be appreciated that while three submersible pumps 560A-560C are shown in FIG. 9A, any number of pumps may be used for a particular piping subsystem and the pumps 560A-560C may also be disposed externally to the fluid storage tank 500. The pumps may be various types of pumps including, but not limited to piston pumps, end-suction pumps, diaphragm pumps, gear pumps, lobed pumps, flexible-vane pumps, nutating pumps, peristaltic pumps, centrifugal pumps, diffuser pumps, propeller pumps, and peripheral pumps.

An exemplary implementation of a hydronics system 501B coupled to a lighting fixture 1000 and a coolant circuit (“lighting loop”) 570 in a controlled agricultural environment 2000D is shown in FIG. 9B. The hydronics system 501B may include a fluid storage tank 500 having contained therein a submersible pump 560. The submersible pump 560 is used to pump relatively cooler fluid coolant 800 into a lighting loop 570, where the fluid coolant 800 is then heated as it passes through the lighting fixture 1000. Subsequently, the relatively hotter fluid coolant 800 exits the lighting loop 570 and enters the fluid storage tank 500 for storage. It should be appreciated that so long as the temperature of the fluid coolant 800 stored in the fluid storage tank 500 is less than the temperature of the fluid coolant 800 entering the fluid storage tank 500 from the lighting loop 570, heat generated by the lighting fixture 1000 may be removed. Over time, if the temperature of the fluid coolant 800 increases, the amount of heat that may be removed may decrease due to a smaller temperature difference. Thus, a heat rejection device may need to be incorporated into the hydronics system 501B to regulate the temperature of the fluid coolant 800 stored in the fluid storage tank 500.

The hydronics system 501B shown in FIG. 9B may also include a secondary heating loop 700C coupled to the portion of the lighting loop 570 where relatively hotter fluid coolant 800 heated by the lighting fixture 1000 flows through (e.g., similar to the hydronics loops 700A and 700B shown in FIG. 4 ). As shown, the secondary heating loop 700C may include a pump 704 and an electric fan with a fan coil 702. The pump 704 generates a flow of the relatively hotter fluid coolant 800 through the fan coil, thus heating the fan coil. The electric fan 702 may then blow heated air towards a plurality of plants 900 located below the lighting fixture 1000 to increase the temperature of the growing area as desired. The second heating loop 700C may be controlled using one or more controllable valves to toggle the secondary heating loop 700C and to adjust the temperature of the air blown by the electric fan 702.

Another exemplary implementation of a hydronics system 501C disposed in a controlled agricultural environment 2000E is shown in FIG. 9C. As shown, the controlled agricultural environment 2000E may have a vertically-stacked multiple-level growing area. Each level of the growing area may include one or more lighting fixtures 1000 coupled to a lighting loop 570. The lighting loop 570 may be coupled to a fluid storage tank 500, which may again contain therein a submersible pump. Similar to the controlled agricultural environment 2000D of FIG. 9B, the hydronics system 501C may include secondary heating loops to separately heat each growing area in each level. The portions of the lighting loop 570 corresponding to each level may be coupled using a plumbing fitting with multiple inlets and outlets. Additionally, the portion of the lighting loop 570 coupled to the fluid storage tank 500 may support a higher flow rate to account for a reduction in flow rate once the fluid coolant 800 flows into each respective level of the growing area.

In some implementations, the lighting fixture 1000 may also function as a sensor platform supporting one or more sensors used to monitor environmental conditions in the controlled agricultural environment. The processor 90 in the lighting fixture 1000 may supply and regulate electrical power to the sensor through the communication ports 1009 (e.g., a USB port and a PoE port). The processor 90 may also include electronics to convert AC power to DC power, as will be described below, thus obviating the need for a separate AC to DC converter in each sensor deployed in the controlled agricultural environment. The processor 90 may also be used to manage data communications, including sending control signals to the sensor and receiving sensory data measured by the sensor for processing and/or transmission to a remote device (e.g., a remote computer or server). In this manner, the lighting fixture 1000 may provide integration of one or more sensors of various types, supplementing the need for separate power and data communications systems. Furthermore, the data measured by the one or more sensors may be used to adjust and control operation of one or more lighting fixtures 1000 (e.g., adjusting the PAR output from the lighting fixture 1000), one or more coolant circuits or other fluid coolant loops (e.g., adjusting the fluid flow through the coolant circuit/lighting loop, heating loop, and cooling loops shown in FIG. 9A), one or more fans, one or more dehumidifiers, or one or more air conditioners in the controlled agricultural environment. In some implementations, various environmental conditions are measured and controlled to provide target vapor pressure deficits in the environment.

An exemplary implementation of a controlled agricultural environment 2000 detailing the integration of various sensors via multiple lighting fixtures 1000 is shown in FIG. 10 . Similar to FIG. 8B, multiple lighting fixtures 1000 may be mounted to a support structure 999 disposed above a plurality of plants 900 arranged on a shelf 902. The controlled agricultural environment 2000 may include one or more dehumidifiers 65, one or more air conditioners 85, and one or more fans 75. A variety of sensors may be supported by the lighting fixture 1000 including, but not limited to an air temperature sensor 80A, a near infrared (NIR) leaf moisture sensor 80B, a relative humidity sensor 80C, a hyperspectral camera 80D, a carbon dioxide sensor 80E, an infrared (IR) leaf temperature sensor 80F, an airflow sensor 80G, and a root zone temperature sensor 80H. The hyperspectral camera 80D refers to a type of camera that measures light within numerous energy bands (e.g., hundreds) where each band is narrower (e.g., 10 nm) than conventional imaging systems. Finite spectral cameras (also referred to as multispectral cameras) may also be used in the controlled agricultural environment 2000 to measure light using a fewer number of energy bands (e.g. 3 to 10) where each band is broader (e.g., greater than 20 nm). The cameras utilized in the controlled agricultural environment 2000 may measure light across various portions of the electromagnetic spectrum including, but not limited to ultraviolet, visible, near-infrared, mid-infrared, and far-infrared wavelengths. The lighting fixture 1000 may also be used to support other auxiliary devices including, but not limited to one or more fans, security cameras, smart phones, and multi-spectral cameras (e.g., to analyze soil moisture and nutrient content). In this manner, various auxiliary devices may be distributed in the controlled agricultural environment due to the flexible placement of communication ports 1009 on the respective lighting fixtures 1000.

The processor 90 may be used to facilitate multiple functionalities pertinent to the operation of the lighting fixture 1000 including, but not limited to power conversion, network connectivity, and data processing in the operation of the lighting fixture 1000. In some implementations, the processor 90 may be comprised of discrete electronics assemblies that are electrically coupled together where each electronics assembly provides one or more distinct functionalities. For example, FIG. 11A shows a block diagram detailing various electronic components and circuitry in the processor 90 to meet these functionalities according to one inventive implementation. The processor 90 may include a control board 100, a network board 200, and a single board computer 300.

The control board 100 may be used to regulate and distribute electrical power to other components of the lighting fixture 1000. As shown in FIG. 11A, the control board 100 may receive AC power through an electrical power port 1010 and convert the AC power to DC power. The control board 100 may then supply DC power and other control signals to other electronics in the lighting fixture 400. For example, the control board 100 may be directly coupled to multiple LED modules 400A, 400B, and 400C via ports/connectors 104A, 104B, and 104C, respectively, on the control board 100. The control board 100 may also be coupled to the network board 200, providing both electrical power and control signals to the network board 200. The control board 100 may also include onboard memory, in which digital signal processing (DSP) firmware 152 is stored to facilitate generation of control signals as described below.

A more detailed block diagram of the control board 100 in FIG. 11A is shown in FIG. 11B. The control board 100 may include a fuse/electromagnetic interference (EMI) filter 153 to provide safety and reduce noise input into the lighting fixture 1000. A rectifier 157 may be used to convert AC power to DC power. An AC line sensor 155 may be used to monitor the voltage and current of the DC power input. DC power may then be passed directly to a bias and control power supply 156, which may be used to distribute DC power to other components of the lighting fixture 1000 including the network board 200 and a digital signal processor (DSP) 150. A DC-DC converter 158 may also be included to supply different voltage inputs to the network board 200. For example, the bias and control power supply 156 may supply 48 V and 5 V to power different circuitry on the network board 200 and the single board computer 300. The 5 V input may be down converted from the 48 V line via the DC-DC converter 158. The DSP 150 may provide control signals by executing the firmware 152 described above to various components including the network board 200, via one or more communications isolators 160. The DSP 150 may also provide control signals to one or more boost converters 162A, 162B, and 162C, which may be used to regulate electricity supplied to the corresponding LED modules 400A-400C via ports 104A-104C. The boost converters 162A-162C may receive DC power directly once converted from AC power via the rectifier 157. The DSP 150 may receive power from the bias and control power supply 156, a voltage and current measurement from the AC line sensor 155, and thermal sensor inputs via the thermal sensor ports 154, which may be used to monitor the temperature of the LED modules 400A-400C.

The network board 200 may be used to manage data communication between the lighting fixture 1000 and various devices coupled to the lighting fixture 1000 including, but not limited to other lighting fixtures 1000 and one or more auxiliary sensors coupled to the lighting fixture 1000. As shown in FIG. 11A, in some implementations, the network board 200 may control one or more PoE ports 1008A, 1008B, 1008C, and 1008D of the lighting fixture 1000. The network board 200 may receive electrical power and control signals from the control board 100 via a control board port 102. The network board 200 may also supply electrical power and control signals to the single board computer 300 via a single board computer port 202. The network board 200 may also support a dedicated Ethernet cable connection 212 through an Ethernet port 213 between the network board 200 and the single board computer 300 to manage data transfer through the PoE ports 1008A-1008D.

A more detailed block diagram of the network board 200 in FIG. 11A is shown in FIG. 11C. The control board port 102 may be used to supply electrical power at different voltages, e.g., 48 V and 5 V, to a PoE controller 206, a power supply 208, and a fan controller and port 210. The control board port 102 may also directly relay control signals from the control board 100 to the single board computer 300 via the single board computer port 202. In some implementations, the control board port 102 may be arranged as a piggyback board to the network board 200. The PoE controller 206 may be used to regulate and supply electrical power to the PoE ports 1008A-1008D. The power supply 208 may supply electrical power to the single board computer 300, through the single board computer port 202, and to an Ethernet switch 204. The Ethernet switch 204 is communicatively coupled to the PoE ports 1008A-1008D and to the single board computer 300 via the Ethernet port 213, which supports the dedicated Ethernet cable connection 212. The Ethernet switch 204 may be used to facilitate receipt and transmission of data and/or control signals to and from the PoE ports 1008A-1008D.

The single board computer 300 may provide several functions to the processor 90 including, but not limited to managing the operation of the control board 100 and the network board 200 and data processing. As shown in FIG. 11A, the single board computer 300 may also be used to support the functionality of USB ports 1012A and 1012B on the lighting fixture 1000. The single board computer 300 may include a memory card 350 that contains (has stored thereon) various data and computer executable code 352 including, but not limited to, session border controller (SBC) software, an operating system, web server software and other web server assets.

The processor 90 may be used to manage the voltage and current supplied to various components of the lighting fixture 1000, e.g., a power cable, the LED modules 400A-400C, in order to reduce the likelihood of damage under different operating conditions. For example, the lighting fixture 1000 may be operated under low voltage conditions where 1200 W may be supplied to the LED modules 400A-400C and 65 W for auxiliary sensors. The power cable used to supply electricity to the lighting fixture 1000 from an external source, e.g., a building electrical supply system, may be rated to sustain a current up to 15 A. The processor 90 may be used to limit the current through the lighting fixture 1000 to 5 A such that three lighting fixtures 400A-400C may be powered by a single power cable 1030. If the current draw of the lighting fixture 1000 approaches 5 A, the processor 90 may reduce the power draw of the lighting fixture. In this manner, the three lighting fixtures 400A-400C may collectively avoid a total current draw that exceeds 15 A, thus reducing the likelihood of damaging the power cable.

In some implementations, the processor 90 may enforce a current draw limit using an active feedback control loop. For instance, the DSP 150 of the control board 100 may be used to actively measure the voltage and current supplied to the lighting fixture 1000 via the AC line sensor 155. Depending on the magnitude and/or rate of change of the measured voltage and current, the DSP 150 may then adjust the voltage and current supplied to each of the LED modules 400A-400C such that the current drawn by the lighting fixture 1000 is maintained below the current draw limit. This process may be conducted in an iterative manner where measurements of the voltage and current supplied to the lighting fixture 1000 and subsequent adjustments to the voltage and current supplied to the LED modules 400A-400C repeatedly occur at a preset timescale. The timescale may vary from about 1 ms to about 60 s. The amount the voltage and current are varied during each increment may also vary according to the rate of change of the voltage and current supplied to the lighting fixture 1000. In some implementations, the stability of the active feedback control loop may be controlled by incorporating a proportional integral differential (PID) controller into the processor 90.

FIGS. 12A-12D, 13, 14A-14H show circuit diagrams of various electrical components of a processor 90 according to one implementation. FIG. 12A shows a circuit diagram of an Ethernet switch 204 from a network board 200 and the electrical connections to PoE ports 1008A-1008D and an Ethernet port 213 for communication to a single board computer 300. FIG. 12A also shows a circuit diagram of a power supply 208 from the network board 200. For visual clarity, FIGS. 12B and 12C show expanded views of the Ethernet switch 204 and the PoE port 1008D from FIG. 12A, respectively. FIG. 12D shows a circuit diagram of a PoE controller 206 from the network board 200. FIG. 13 shows a circuit diagram of a single board computer 300 detailing various input and output connections. FIG. 14A shows circuit diagrams for an electrical power port 1010, fuse/EMI filter 153, a rectifier 154, and a first portion of a bias and control power supply 156 from a control board 100. FIG. 14B shows a second portion of the bias and control power supply 156 shown in FIG. 14A. FIGS. 14C-14F show a DC-DC converter 158, an AC line sensor 155, a DSP 150, and thermal sensor ports 154 from the control board 100. FIGS. 14G and 14H show circuit diagrams of an exemplary boost circuit 162A from the control board 100.

The lighting fixture 1000 disclosed herein may also be utilized in a leased lighting system where a customer pays a recurring fee to rent and operate the lighting fixture 1000 (e.g., provide lighting using the lighting fixture 1000). In this system, the costs typically associated with purchasing the lighting fixture 1000 hardware and installation may be substantially reduced, thus providing substantial savings to the customer. The manufacturer providing the operation of the lighting fixture 1000 may earn a profit over time through continuing payments by the customer. In some implementations, the leased lighting system may be based on payment of a fee to operate the lighting fixture 1000 for a preset period of time. The lighting fixture 1000 may be communicatively coupled to a server via the processor 90. The server may remotely regulate operation of the lighting fixture, enabling the lighting fixture 1000 to provide lighting so long as the customer provides necessary payment to maintain the lease.

An exemplary implementation of a contract enforcement method where the lighting fixture 1000 is communicatively coupled to a license server 600 is shown in FIG. 15A. As shown, the license server 600 may include a database 602 containing information including, but not limited to a serial number for one or more lighting fixtures 1000 installed by a customer and a customer status (e.g., a payment status) for the customer to which the one or more lighting fixtures 1000 are leased. The database may also include a pre-shared key 604, which is also installed onto each lighting fixture 1000, e.g., such as in protected internal storage of the DSP 150 of the lighting fixture 1000, by the manufacturer, together with a timer, prior to shipment to the customer. Upon initial payment by the customer, the manufacturer may setup an initial timer update in the database 1000 to provide for some time period for initial lighting, after which an additional lease payment is required. Once the lighting fixture 1000 is deployed to the customer, the expiration of the timer may trigger a license update process. Once the additional lease payment is made, the manufacturer operating the license server 600 may update the database 602 with a new timer value, which is communicated to the lighting fixture 1000. Communication may occur via a proprietary communication protocol.

An exemplary implementation of a process to update a license for a leased lighting model with one or more lighting fixtures 1000 is shown in FIG. 15B. In this exemplary process, the DSP 150 and the single board computer 300 of the processor 90 may be coupled to the license server 600 and database 602 via the Internet to facilitate operation by the manufacturer of the one or more lighting fixtures 1000 or a leasing agent. As described above, the pre-shared key 604 and license timer may be stored in the protected internal storage of the DSP 150 by the manufacturer together with the serial number of the lighting fixture 1000. The single board computer 300 may periodically check the status of the license timer. Once the license timer is near expiration, the single board computer 300 may initiate with the DSP 150 a license update request. This request may include a “challenge packet” generated by the DSP 150, which is forwarded by the single board computer 300 to the license server 600. The challenge packet may include encrypted information based, at least in part, on the serial number of the lighting fixture 1000 and a temporary random key generated using a noise accumulator. The challenge packet may then be decrypted by the license server 600. If the challenge packet is found to be valid and payment is made for additional lighting, the license server 600 may then determine a new allowed timer value. The new allowed timer value may then be encrypted and sent back to the single board computer 300, which passes the encrypted timer value to the DSP 150. The DSP 150 may then decrypt the new timer value based on the pre-shared key 604. If the new timer value is found to be valid, the DSP 150 may update the license timer stored in the protected internal storage of the DSP 150.

CONCLUSION

While various inventive implementations have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive implementations described herein. More generally, those skilled in the art will readily appreciate that all parameters and configurations described herein are meant to be exemplary inventive features and that other equivalents to the specific inventive implementations described herein may be realized. It is, therefore, to be understood that the foregoing implementations are presented by way of example and that, within the scope of the appended claims and equivalents thereto, inventive implementations may be practiced otherwise than as specifically described and claimed. Inventive implementations of the present disclosure are directed to each individual feature, system, article, and/or method described herein. In addition, any combination of two or more such features, systems, articles, and/or methods, if such features, systems, articles, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

The above-described implementations can be implemented in multiple ways. For example, implementations may be implemented using hardware, software or a combination thereof. When implemented in software, the software code can be executed on any suitable processor or collection of processors, whether provided in a single computer or distributed among multiple computers. Further, it should be appreciated that a computer may be embodied in any of a number of forms, such as a rack-mounted computer, a desktop computer, a laptop computer, or a tablet computer. Additionally, a computer may be embedded in a device not generally regarded as a computer but with suitable processing capabilities, including a Personal Digital Assistant (PDA), a smart phone or any other suitable portable or fixed electronic device.

Also, a computer may have one or more input and output devices. These devices can be used, among other things, to present a user interface. Examples of output devices that can be used to provide a user interface include printers or display screens for visual presentation of output and speakers or other sound generating devices for audible presentation of output. Examples of input devices that can be used for a user interface include keyboards, and pointing devices, such as mice, touch pads, and digitizing tablets. As another example, a computer may receive input information through speech recognition or in other audible format. Such computers may be interconnected by one or more networks such as Internet. The various methods or processes outlined herein may be coded as software that is executable on one or more processors that employ any one of a variety of operating systems or platforms. Additionally, such software may be written using any of a number of suitable programming languages and/or programming or scripting tools, and also may be compiled as executable machine language code or intermediate code that is executed on a framework or virtual machine.

In this respect, various inventive concepts may be embodied as a computer readable memory or storage medium (or multiple computer readable storage media) (e.g., a computer memory, one or more floppy discs, compact discs, optical discs, magnetic tapes, flash memories, circuit configurations in Field Programmable Gate Arrays or other semiconductor devices, or other non-transitory medium or tangible computer storage medium) encoded with one or more programs that, when executed on one or more computers or other processors, perform methods that implement the various implementations of the invention discussed above. The computer readable medium or media can be transportable, such that the program or programs stored thereon can be loaded onto one or more different computers or other processors to implement various aspects of the present invention as discussed above.

Unless otherwise indicated, the terms “program” or “software” are used herein in a generic sense to refer to any type of computer code or set of computer-executable instructions that can be employed to program a computer or other processor to implement various aspects of implementations as discussed above. Additionally, it should be appreciated that according to one aspect, one or more computer programs that when executed perform methods of the present invention need not reside on a single computer or processor, but may be distributed in a modular fashion amongst a number of different computers or processors to implement various aspects of the present invention.

Computer-executable instructions may be in many forms, such as program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Typically, the functionality of the program modules may be combined or distributed as desired in various implementations.

Also, data structures may be stored in computer-readable media in any suitable form. For simplicity of illustration, data structures may be shown to have fields that are related through location in the data structure. Such relationships may likewise be achieved by assigning storage for the fields with locations in a computer-readable medium that convey relationship between the fields. However, any suitable mechanism may be used to establish a relationship between information in fields of a data structure, including through the use of pointers, tags or other mechanisms that establish relationship between data elements. In some implementations, a schema-minimal storage system may be implemented in a relational database environment using key-value storage versus defined data structures.

Also, various inventive concepts may be embodied as one or more methods, of which an example has been provided. The acts performed as part of the method may be ordered in any suitable way. Accordingly, implementations may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative implementations.

All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety.

All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms.

The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and/or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to “A and/or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one implementation, to A only (optionally including elements other than B); in another implementation, to B only (optionally including elements other than A); in yet another implementation, to both A and B (optionally including other elements); etc.

As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and/or” as defined above. For example, when separating items in a list, “or” or “and/or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of” or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law.

As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) can refer, in one implementation, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another implementation, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another implementation, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03. 

The invention claimed is:
 1. A lighting fixture, comprising: an extruded aluminum housing; at least one light source mechanically supported by the extruded aluminum housing; and at least one copper pipe thermally coupled to the extruded aluminum housing to carry a fluid coolant, wherein: the at least one light source includes at least one LED light source; during operation of the lighting fixture, the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture; the fluid coolant does not contact the extruded aluminum housing; the extruded aluminum housing includes at least one cavity to contain control circuitry to control the at least one light source; and the lighting fixture does not include any seals for the fluid coolant or O-rings for the fluid coolant within the at least one cavity of the extruded aluminum housing.
 2. The lighting fixture of claim 1, wherein the extruded aluminum housing includes a light spine to facilitate mechanical coupling of the lighting fixture to at least one support structure of a controlled agricultural environment.
 3. The lighting fixture of claim 1, further comprising at least one port to provide auxiliary DC power to at least one auxiliary device coupled to the at least one port.
 4. A system, comprising: at least one lighting fixture according to claim 3; and at least one sensor coupled to the at least one port.
 5. The system of claim 4, wherein the at least one sensor includes at least one of: an air temperature sensor; a near infrared (NIR) sensor; a relative humidity sensor; a camera; a carbon dioxide (CO2) sensor; or an infrared (IR) sensor.
 6. The lighting fixture of claim 3, wherein the at least one port provides the auxiliary DC power and data coupling for the at least one auxiliary device coupled to the at least one port.
 7. A lighting fixture, comprising: an extruded aluminum housing; at least one light source mechanically supported by the extruded aluminum housing; and at least one copper pipe thermally coupled to the extruded aluminum housing to carry a fluid coolant, wherein: the at least one light source includes at least one LED light source; during operation of the lighting fixture, the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture; the fluid coolant does not contact the extruded aluminum housing; the extruded aluminum housing includes at least one channel formed therein; and the at least one copper pipe is press-fit into the at least one channel of the extruded aluminum housing so as to establish a thermal connection between the at least one copper pipe and the extruded aluminum housing.
 8. The lighting fixture of claim 7, wherein the lighting fixture does not include any internal seals for the fluid coolant.
 9. The lighting fixture of claim 7, wherein the lighting fixture does not include any internal O-rings for the fluid coolant.
 10. The lighting fixture of claim 7, wherein the extruded aluminum housing includes a light spine to facilitate mechanical coupling of the lighting fixture to at least one support structure of a controlled agricultural environment.
 11. The lighting fixture of claim 7, further comprising at least one port to provide auxiliary DC power to at least one auxiliary device coupled to the at least one port.
 12. The lighting fixture of claim 11, wherein the at least one port provides the auxiliary DC power and data coupling for the at least one auxiliary device coupled to the at least one port.
 13. The lighting fixture of claim 11, wherein the at least one port comprises at least one of: at least one Power over Ethernet (PoE) port to facilitate power coupling and data coupling of at least one first external device to the lighting fixture; or at least one Universal Serial Bus (USB) port to facilitate coupling of at least one second external device to the lighting fixture.
 14. A system, comprising: at least one lighting fixture according to claim 11; and at least one sensor coupled to the at least one port.
 15. The system of claim 14, wherein the at least one sensor includes at least one of: an air temperature sensor; a near infrared (NIR) sensor; a relative humidity sensor; a camera; a carbon dioxide (CO2) sensor; or an infrared (IR) sensor.
 16. A lighting fixture, comprising: an extruded aluminum housing; at least one light source mechanically supported by the extruded aluminum housing; and at least one copper pipe thermally coupled to the extruded aluminum housing to carry a fluid coolant, wherein: the at least one light source includes at least one LED light source; during operation of the lighting fixture, the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture; the fluid coolant does not contact the extruded aluminum housing; and the at least one copper pipe includes a first copper pipe and a second copper pipe both thermally coupled to the extruded aluminum housing to carry the fluid coolant.
 17. The lighting fixture of claim 16, wherein: the first copper pipe and the second copper pipe carry the fluid coolant in a coolant circuit when the fluid coolant is present, such that the fluid coolant flows in different directions respectively through the first copper pipe and the second copper pipe.
 18. The lighting fixture of claim 16, wherein the lighting fixture does not include any internal seals for the fluid coolant.
 19. The lighting fixture of claim 16, wherein the lighting fixture does not include any internal O-rings for the fluid coolant.
 20. The lighting fixture of claim 16, wherein the extruded aluminum housing includes a light spine to facilitate mechanical coupling of the lighting fixture to at least one support structure of a controlled agricultural environment.
 21. The lighting fixture of claim 16, further comprising at least one port to provide auxiliary DC power to at least one auxiliary device coupled to the at least one port.
 22. The lighting fixture of claim 21, wherein the at least one port provides the auxiliary DC power and data coupling for the at least one auxiliary device coupled to the at least one port.
 23. The lighting fixture of claim 21, wherein the at least one port comprises at least one of: at least one Power over Ethernet (PoE) port to facilitate power coupling and data coupling of at least one first external device to the lighting fixture; or at least one Universal Serial Bus (USB) port to facilitate coupling of at least one second external device to the lighting fixture.
 24. A system, comprising: at least one lighting fixture according to claim 21; and at least one sensor coupled to the at least one port.
 25. The system of claim 24, wherein the at least one sensor includes at least one of: an air temperature sensor; a near infrared (NIR) sensor; a relative humidity sensor; a camera; a carbon dioxide (CO2) sensor; or an infrared (IR) sensor.
 26. A lighting fixture, comprising: an extruded aluminum housing; at least one light source mechanically supported by the extruded aluminum housing; and at least one copper pipe thermally coupled to the extruded aluminum housing to carry a fluid coolant, wherein: the at least one light source includes at least one LED light source; during operation of the lighting fixture, the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture; and the fluid coolant does not contact the extruded aluminum housing, the lighting fixture further comprising at least one port to provide auxiliary DC power to at least one auxiliary device coupled to the at least one port, wherein the at least one port comprises at least one of: at least one Power over Ethernet (PoE) port to facilitate power coupling and data coupling of at least one first external device to the lighting fixture; or at least one Universal Serial Bus (USB) port to facilitate coupling of at least one second external device to the lighting fixture.
 27. A controlled agricultural environment, comprising: a system comprising: at least one lighting fixture comprising: an extruded aluminum housing; at least one light source mechanically supported by the extruded aluminum housing; at least one copper pipe thermally coupled to the extruded aluminum housing to carry a fluid coolant and at least one port to provide auxiliary DC power to at least one auxiliary device coupled to the at least one port; wherein: the at least one light source includes at least one LED light source; during operation of the lighting fixture, the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture; and the fluid coolant does not contact the extruded aluminum housing; and at least one sensor coupled to the at least one port; at least one cooling tower; and at least one fluid circuit coupled to the at least one cooling tower and the at least one copper pipe of the at least one lighting fixture to carry the fluid coolant between the at least one cooling tower and the at least one lighting fixture.
 28. The controlled agricultural environment of claim 27, further comprising a dehumidifier.
 29. The controlled agricultural environment of claim 28, wherein the dehumidifier is coupled to the at least one fluid circuit.
 30. The controlled agricultural environment of claim 27, further comprising at least one fan.
 31. The controlled agricultural environment of claim 30, wherein: the at least one lighting fixture includes a fan controller; and the at least one fan is communicatively coupled to the fan controller of the at least one lighting fixture.
 32. The controlled agricultural environment of claim 31, wherein the at least one fan is coupled to the at least one port of the at least one lighting fixture.
 33. The controlled agricultural environment of claim 27, wherein the controlled agricultural environment does not include an air conditioner comprising an air conditioning condenser, an air conditioning compressor, and/or an air conditioning coil.
 34. The controlled agricultural environment of claim 27, further comprising: a building structure in which the system is disposed; at least one support structure arranged in the building structure for supporting the system, wherein the at least one lighting fixture is mechanically coupled to the at least one support structure; and at least one shelving structure to support a plurality of plants, the at least one shelving structure arranged in the building structure with respect to the at least one support structure to facilitate irradiation of the plurality of plants by photosynthetically active radiation (PAR) provided by the at least one lighting fixture. 